CXCL8 and osteoarthritis, knee: The level of pain caused by knee osteoarthritis is closely related to the levels of inflammatory factors in the synovial fluid, such as IL-6, IL-1β, TNF-α, IL-8, etc. A study on the correlation between immune biomarkers and early- and late-stage MRI of KOA demonstrated a negative correlation between IL-6 levels and WOMAC scores.